Optimize first render time of the RoboVM backend. Fixes #6971 (#6972)

CHANGES

@@ -3,6 +3,7 @@
 - [BREAKING CHANGE] Android: Immersive mode is now true by default. Set `useImmersiveMode` config to `false` to disable it. 
 - [BREAKING CHANGE] iOS: `hideHomeIndicator` set to `false` by default (was `true`).
 - [BREAKING CHANGE] iOS: `screenEdgesDeferringSystemGestures` set to `UIRectEdge.All` by default (was `UIRectEdge.None`).
+- [BREAKING CHANGE] iOS: `ApplicationListener.create` and first `resize` are now called within `UIApplicationDelegate.didFinishLaunching`. Allows for earlier rendering and prevents black screen frames after launch screen. NOTE: App will get terminated if this method is blocked for more than 10-20 sec. 
 - [BREAKING CHANGE] Actor#localToAscendantCoordinates throws an exception if the specified actor is not an ascendant.
 - [BREAKING CHANGE] WidgetGroup#hit first validates the layout.
 - iOS: Add new MobiVM MetalANGLE backend

backends/gdx-backend-robovm-metalangle/src/com/badlogic/gdx/backends/iosrobovm/IOSApplication.java

@@ -142,7 +142,12 @@ final boolean didFinishLaunching (UIApplication uiApp, UIApplicationLaunchOption
 		Gdx.net = this.net;
 		this.input.setupPeripherals();
 		this.uiWindow.setRootViewController(this.graphics.viewController);
+		this.graphics.updateSafeInsets();
 		Gdx.app.debug("IOSApplication", "created");
+		listener.create();
+		listener.resize(this.graphics.getWidth(), this.graphics.getHeight());
+		// make sure the OpenGL view has contents before displaying it
+		this.graphics.view.display();
 		return true;
 	}
 

backends/gdx-backend-robovm-metalangle/src/com/badlogic/gdx/backends/iosrobovm/IOSGraphics.java

@@ -186,6 +186,14 @@ public void draw (CGRect rect) {
 		// time + FPS
 		lastFrameTime = System.nanoTime();
 		framesStart = lastFrameTime;
+		// enable OpenGL
+		makeCurrent();
+		// OpenGL glViewport() function expects backbuffer coordinates instead of logical coordinates
+		gl20.glViewport(0, 0, screenBounds.backBufferWidth, screenBounds.backBufferHeight);
+		String versionString = gl20.glGetString(GL20.GL_VERSION);
+		String vendorString = gl20.glGetString(GL20.GL_VENDOR);
+		String rendererString = gl20.glGetString(GL20.GL_RENDERER);
+		glVersion = new GLVersion(Application.ApplicationType.iOS, versionString, vendorString, rendererString);
 		appPaused = false;
 	}
 
@@ -214,25 +222,11 @@ public void pause () {
 		app.listener.pause();
 	}
 
-	boolean created = false;
-
 	public void draw (MGLKView view, CGRect rect) {
 		makeCurrent();
 		// massive hack, GLKView resets the viewport on each draw call, so IOSGLES20
 		// stores the last known viewport and we reset it here...
 		gl20.glViewport(IOSGLES20.x, IOSGLES20.y, IOSGLES20.width, IOSGLES20.height);
-		if (!created) {
-			// OpenGL glViewport() function expects backbuffer coordinates instead of logical coordinates
-			gl20.glViewport(0, 0, screenBounds.backBufferWidth, screenBounds.backBufferHeight);
-			String versionString = gl20.glGetString(GL20.GL_VERSION);
-			String vendorString = gl20.glGetString(GL20.GL_VENDOR);
-			String rendererString = gl20.glGetString(GL20.GL_RENDERER);
-			glVersion = new GLVersion(Application.ApplicationType.iOS, versionString, vendorString, rendererString);
-			updateSafeInsets();
-			app.listener.create();
-			app.listener.resize(getWidth(), getHeight());
-			created = true;
-		}
 		if (appPaused) {
 			return;
 		}

backends/gdx-backend-robovm-metalangle/src/com/badlogic/gdx/backends/iosrobovm/IOSUIViewController.java

@@ -27,8 +27,8 @@ protected IOSUIViewController (IOSApplication app, IOSGraphics graphics) {
 	}
 
 	@Override
-	public void viewWillAppear (boolean arg0) {
-		super.viewWillAppear(arg0);
+	public void viewWillAppear (boolean animated) {
+		super.viewWillAppear(animated);
 		// start GLKViewController even though we may only draw a single frame
 		// (we may be in non-continuous mode)
 		setPaused(false);
@@ -74,7 +74,7 @@ public void viewDidLayoutSubviews () {
 		final IOSScreenBounds newBounds = app.computeBounds();
 		graphics.screenBounds = newBounds;
 		// Layout may happen without bounds changing, don't trigger resize in that case
-		if (graphics.created && (newBounds.width != oldBounds.width || newBounds.height != oldBounds.height)) {
+		if (newBounds.width != oldBounds.width || newBounds.height != oldBounds.height) {
 			graphics.makeCurrent();
 			graphics.updateSafeInsets();
 			graphics.gl20.glViewport(0, 0, newBounds.backBufferWidth, newBounds.backBufferHeight);

backends/gdx-backend-robovm/src/com/badlogic/gdx/backends/iosrobovm/IOSApplication.java

@@ -149,7 +149,16 @@ final boolean didFinishLaunching (UIApplication uiApp, UIApplicationLaunchOption
 		this.input.setupPeripherals();
 
 		this.uiWindow.setRootViewController(this.graphics.viewController);
+		this.graphics.updateSafeInsets();
+
 		Gdx.app.debug("IOSApplication", "created");
+
+		listener.create();
+		listener.resize(this.graphics.getWidth(), this.graphics.getHeight());
+
+		// make sure the OpenGL view has contents before displaying it
+		this.graphics.view.display();
+
 		return true;
 	}
 

backends/gdx-backend-robovm/src/com/badlogic/gdx/backends/iosrobovm/IOSGraphics.java

@@ -185,6 +185,16 @@ public void draw (CGRect rect) {
 		lastFrameTime = System.nanoTime();
 		framesStart = lastFrameTime;
 
+		// enable OpenGL
+		makeCurrent();
+		// OpenGL glViewport() function expects backbuffer coordinates instead of logical coordinates
+		gl20.glViewport(0, 0, screenBounds.backBufferWidth, screenBounds.backBufferHeight);
+
+		String versionString = gl20.glGetString(GL20.GL_VERSION);
+		String vendorString = gl20.glGetString(GL20.GL_VENDOR);
+		String rendererString = gl20.glGetString(GL20.GL_RENDERER);
+		glVersion = new GLVersion(Application.ApplicationType.iOS, versionString, vendorString, rendererString);
+
 		appPaused = false;
 	}
 
@@ -215,28 +225,12 @@ public void pause () {
 		app.listener.pause();
 	}
 
-	boolean created = false;
-
 	public void draw (GLKView view, CGRect rect) {
 		makeCurrent();
 		// massive hack, GLKView resets the viewport on each draw call, so IOSGLES20
 		// stores the last known viewport and we reset it here...
 		gl20.glViewport(IOSGLES20.x, IOSGLES20.y, IOSGLES20.width, IOSGLES20.height);
 
-		if (!created) {
-			// OpenGL glViewport() function expects backbuffer coordinates instead of logical coordinates
-			gl20.glViewport(0, 0, screenBounds.backBufferWidth, screenBounds.backBufferHeight);
-
-			String versionString = gl20.glGetString(GL20.GL_VERSION);
-			String vendorString = gl20.glGetString(GL20.GL_VENDOR);
-			String rendererString = gl20.glGetString(GL20.GL_RENDERER);
-			glVersion = new GLVersion(Application.ApplicationType.iOS, versionString, vendorString, rendererString);
-
-			updateSafeInsets();
-			app.listener.create();
-			app.listener.resize(getWidth(), getHeight());
-			created = true;
-		}
 		if (appPaused) {
 			return;
 		}

backends/gdx-backend-robovm/src/com/badlogic/gdx/backends/iosrobovm/IOSUIViewController.java

@@ -23,8 +23,8 @@ protected IOSUIViewController (IOSApplication app, IOSGraphics graphics) {
 	}
 
 	@Override
-	public void viewWillAppear (boolean arg0) {
-		super.viewWillAppear(arg0);
+	public void viewWillAppear (boolean animated) {
+		super.viewWillAppear(animated);
 		// start GLKViewController even though we may only draw a single frame
 		// (we may be in non-continuous mode)
 		setPaused(false);
@@ -70,7 +70,7 @@ public void viewDidLayoutSubviews () {
 		final IOSScreenBounds newBounds = app.computeBounds();
 		graphics.screenBounds = newBounds;
 		// Layout may happen without bounds changing, don't trigger resize in that case
-		if (graphics.created && (newBounds.width != oldBounds.width || newBounds.height != oldBounds.height)) {
+		if (newBounds.width != oldBounds.width || newBounds.height != oldBounds.height) {
 			graphics.makeCurrent();
 			graphics.updateSafeInsets();
 			graphics.gl20.glViewport(0, 0, newBounds.backBufferWidth, newBounds.backBufferHeight);